Margaret Thatcher would not have voted for Brexit, her former private secretary has said.

Caroline Slocock, who worked for the former Tory Prime Minister in 10 Downing Street from 1989 to 1991, said she would have preferred to stay in the European Union and fight to reform it.

Leave supporters have sometimes used Baroness Thatcher’s euroscepticism in the later years of her premiership and in her retirement to suggest she would have voted to leave the European Union.

However, speaking to Chopper’s Brexit Podcast, Ms Slocock said that she would not have voted to leave the EU.

The comments echo those of Lord Powell of Bayswater, Lady Thatcher’s most trusted foreign adviser in Number 10, who said the former PM would have voted to stay in the EU in September 2016.

Ms Slocock said: “My view is that she wouldn’t and I share this view with Charles Powell who advised her on foreign affairs as private secretary when I was there.

“My justification for that is she would not have got into this mess in the first place. She had form and the form was to stay in and fight.

“On the rebate she fought for five years to get the right deal – and I just think that David Cameron walked away far too early from those discussions with the EU.

“She would have done a much better job and we probably would not have had a referendum at all.

“She was very much against the idea of the European super state. She said in her famous Bruges speech that she had not rolled back the frontiers of state in Britain to see them rolling forward in Europe.

“She was angry about it but the fundamental thing is that she was fighting her corner, she wasn’t walking away and she valued immensely the trading relationship that we have with the EU.

“She – who regarded the single market as her greatest achievement in Europe – would just be non-plussed to be finding us walking away from trading relationships with effectively 70 per cent of our trade is with Europe or through European trade agreements – doing that speculatively in the hope that we will get better trading agreements elsewhere.

“The mistake of the government was to sign article 50 – now it has got no real negotiating strength - if you are inside the EU threatening to leave you have got a much better negotiating position.”

Also on Chopper’s Brexit Podcast, from 6am on Friday morning, Jake Berry MP, the Northern Powerhouse minister, supported calls for Donald Trump to visit the north of England when he visits the UK later this summer.

Pointing out that Ben Houchen, the Tory mayor for Tees Valley, has invited Mr Trump to visit his region, Mr Berry said it was important that the UK sought a better trading relationship with the US “whatever people’s views of Donald Trump”.

Mr Berry added: “I would be delighted if Donald Trump visits the north of England. He would be probably welcomed in manufacturing areas who want to build that very close trading relationship and we shouldn’t let our personal views whatever they may be about his politics stand in the way of having a successful visit for our closest ally and that visit must be focused on creating a close trading relationship between the manufacturers of the north and the manufacturers of the United States.”

Other guests include George Freeman MP, ex-chairman of the Conservative policy board, Jeremy Warner, the Telegraph’s Assistant Editor and Ed Malnick, the Telegraph’s Whitehall Editor.

The podcast also features the first #BrexitPoems which were submitted by Twitter.